import java.util.ArrayList;
import java.util.Collections;

public class CollectionsCode {
    /*
    * Coolections是数组集合的操作方法 （集合工具类）
    *
    * addAll 批量添加元素
    * shiffle 打乱list集合元素的顺序
    * */
    public static void main(String[] args) {
        ArrayList<String> list = new ArrayList<>();
        Collections.addAll(list,"1","2","3","4","5","6","7","8","9");

        Collections.shuffle(list);

        System.out.println(list);


    }
}
